NE-CPA-FSA-Worksheet-10 Nebraska Wetland Functional ......U.S. DEPARTMENT OF AGRICULTURE Natural Resources Conservation Service NE-CPA-FSA-Worksheet-10 2/09 Appendix A Definition:

U.S. DEPARTMENT OF AGRICULTURENatural Resources Conservation Service

NE-CPA-FSA-Worksheet-102/09

Topography of Floodplain

Vegetation Density

Wetland Modifications

Wooded Riverine (Appendix C)

Sandhills Wetlands (Appendix D)Slope Wetlands (Appendix E)Other Wetlands (Appendix F)

Source Area of FlowSediment DepositionNative Plant Composition

Functional assessments will be used for analyzing functions and values of wetland effects such as with mitigation, restoration and enhancement planning and for answering Step 6. of the Nebraska Minimal Effect Procedure (NE-CPA-FSA-Worksheet-9).

Separate functional assessments apply to different landforms as listed below. Refer to the descriptions of the landforms to determine which model applies. If it is determined that your situation does not fit one of the landforms then contact the State Wildlife Biologist for further guidance and the possibility to use the "Other Wetland " functional assessment. For each functional assessment there is a corresponding Measurement Condition Index that assists you in rating each variable.

Playa Wetlands

Buffer Continuity and Width


Native Plant Composition

Wetlands that occur within a topographic depression that allow the accumulation of surface water. Depressional wetlands often are closed basins without any direct inlet or outlet; however, it is possible that either or both of these will exist within a playa wetland. The predominant hydrodynamic activity is a seasonal vertical fluctuation of water levels.

Floodplain Land Use

Hydrology Alterations

Landforms

Sediment Deposition

Nebraska Wetland Functional Assessment Protocol

Intermittent StreamWetlands that occur within low gradient, fine substrate riverine ecosystems that have intermittent or seasonal flow regimes within defined channels. These generally include the lower segments of first order streams and second order streams with the characteristic flow regime. These ecosystems typically convey surface water within a defined channel. In normal precipitation years, their flow regime is seasonal and typically occurs in the spring and summer. Surface flow will cease, usually in late summer or early fall. During years of above-normal precipitation, they may exhibit year-round flow. Conversely, these stream systems may be dry for extended periods during years of drought.


Functions being evaluated: Flood Attenuation, Wildlife HabitatVariables used:

Playa Wetlands (Appendix B)Intermittent Stream (Appendix A)

Functions being evaluated: Water Storage, Wildlife HabitatVariables used:

Landformspage 1 of 2




Vegetation Strata


Wooded Riverine

Functions being evaluated: Flood Attenuation, Wildlife Habitat

Functions being evaluated: Ground Water Storage, Wildlife HabitatVariables used:

Floodplain Land Use


Sediment DepositionNative Plant Composition

Other Wetlands

Wetlands that are normally found where there is a surface discharge of groundwater on sloping land. Typically ocurrs at the upper end of small drainage courses or sidehill seeps along breaks associated with larger streams. A restrictive soil layer that has slow permeability restricts downward movement of water causing water to move laterally and discharge at the surface. Slope wetlands are typically not capable of depressional storage because of a lack of closed contours but may contain small basins which hold water for brief periods (less than 7 days) during precipitation events. Principal water sources are groundwater return flow and inter-flow from surrounding uplands, as well as precipitation. Climate ranges from semi-arid to subhumid. The slope wetland class has been defined by Brinson, et. al. (1993). After testing and revising the model, the reference domain for its application may be expanded.

Variables used:



Variables used:

If it is determined that your situation does not fit one of the other landforms then contact the State Wildlife Biologist for further guidance and the possibility to use the "Other Wetlands " functional assessment. (i.e. saline wetlands, fens, wet meadows)


Wetlands that occur in areas with relatively sandy parent material and soils. The water source for these wetlands is often elevated groundwater but surface runoff also contributes. A wide range of conditions are possible from closed basins to pronounced inlets/outlets and saturated soils to areas with substantial open water. Water levels will fluctuate during the year (seasonally) and between years depending upon groundwater levels and precipitation.

Sandhills Wetlands

Vegetation DensityNative Plant CompositionBuffer Continuity and Width

Source Area of Flow

Vegetation Density

Wetlands that occur within larger riverine ecosystems that have perennial flow regimes within defined channels. These include second order streams with the characteristic flow regime and points lower within the watershed. These ecosystems typically convey surface water within a defined channel with periodic out-of-bank flow during high rainfall events. Large wetlands within the floodplain may have similarities to other wetland classes (i.e. old "oxbows" may have playa wetland characteristics).

Slope Wetlands

Sediment Deposition

Functions being evaluated: Water Quality, Wildlife Habitat

Native Plant Composition Source Area of Flow

Sediment Deposition

Landformspage 2 of 2



Appendix A

Post-Project

No Minimal Effect granted

No Minimal Effect grantedMinimal Effect decision:

*Vhalt = the square root of (Hs x Hw)

[4(Vhalt) + (Vsed + Vtopo)/2 + (Vbuff + Vfuse)/2] then divide by 6

Wildlife Habitat =

Flood Attenuation =

[3(Vhalt) + Vnplant + (Vbuff + Vfuse)/2 + (Vsed + Vtopo)/2] then divide by 6

Vtopo

Vfuse


Floodplain Land Use

Hs

Hw

Stream Hydrology

Minimal Effect threshold is 0.10 (There must be less than a 0.10 decrease for BOTH Flood Attenuation and Wildlife Habitat from Pre-Project conditions)Notes:

Final Rating

Final Rating

With Conditions

Site Conditions:

For each variable, use the coinciding measurement condition index sheet to arrive at a rating from 0-1.0 that most closely resembles the present or planned condition. Then, take that number and multipy it by the weight factor and enter that value in the score column.

County:Location:

Proposed Action

Landowner:

Proposed Conditions (if any)


Intermittent Stream Functional Assessment Date:

Planner:

Pre-Project

Post-Project

Project With Conditions

Variables (Use Measurement Condition Index worksheet to answer this

section. Answers will auto-fill from there)

Sediment Deposition



Vbuff

Vsed

Vnplant

Wetland Hydrology

Vhalt*

use for calculating

Vhalt

Intermittent Streampage 1 of 7



Appendix A

Definition: The presence of man-made, surface and/or subsurface alterations that are on the floodplain within or immediately adjacent to the stream segment/linear wetland. These alterations primarily impact the hydrology of the stream segment/linear wetland. Surface alterations may include channelization, dams, diversions, or dikes. Subsurface alterations may include tile drainage or ditches greater than two feet in depth. Flood plain alterations within 1/4 mile (1,320 feet) parallel to or upstream are considered significant to hydrology and must be considered.

Condition Index Rating Pre-project Project w/ conditionsPost-project

0

0.25

Flood plain has not been physically manipulated. No surface alterations (such as constructed channels, dams, dikes, diversions, dugouts, or fill) or subsurface alterations (such as tile drainage) present.

One or more surface alterations (constructed channels, dams, dikes, diversions, dugouts, or fill) are present at a distance greater than 1/8 mile (660 feet) up to 1/4 mile (1,320 feet) parallel to or upstream from the stream/linear wetland. Such alteration(s) partially divert (>50 - 75%) or retard the flow of surface water, particularly water from high flow events, away from the wetland. No subsurface alterations are present.

One or more surface alterations (constructed channels, dams, dikes, diversions, dugouts, or fill) are present at a distance greater than 1/4 mile (1,320 feet) parallel to or upstream from the stream/linear wetland. Such alteration(s) partially divert (>25 - 50%) or retard the flow of surface water, particularly water from high flow events, away from the wetland. No subsurface alterations are present.

One or more surface alterations (constructed channels, dams, dikes, diversions, dugouts, or fill) are present within 1/8 mile (660 feet) parallel to or upstream from the stream/linear wetland. Such alteration(s) are designed to divert or retard >75% of the surface water flow, particularly water from high flow events, away from the wetland,AND/ORA subsurface drainage feature (such as drain tile) is adjacent and parallel to the wetland. Flood plain hydrology has been altered such that all surface and/or subsurface flow to the wetland has been eliminated. (Alterations include channelization and lining, or complete diversion or drainage of surface and/or subsurface water sources.)

0.01

Intermittent Stream Functional Assessment

0.75

0.5

Measurement Condition IndexHs: Stream Hydrology

1.0

A water impoundment structure is situated downstream from the stream segment/linear wetland such that wetland hydrology has been enhanced or degraded beyond what it would normally be. No structures are present parallel to or upstream that would affect hydrology or hydrology impacted <25%.

Assessment area: Stream reach and adjacent floodplain including alterations 1/4 mile above and below stream reach being assessed.




Appendix A

Intermittent Stream Functional AssessmentMeasurement Condition Index

Post-project Project w/ conditions

Assessment area: Wetlands located within adjacent floodplain. If there are no wetlands present in the assessment area then give this variable the same Condition Index Rating as Stream Hydrology.

Hw: Wetland HydrologyDefinition: The presence of man-made, surface and/or subsurface alterations that are within or adjacent to wetlands located on the floodplain but not within the flowing channel. These alterations primarily impact the hydrology of the wetland. Surface alterations may include shallow ditches, fill, or dams/dikes. Subsurface alterations may include tile drainage or ditches greater than two feet in depth.

1.0 Wetland has not been physically manipulated. No surface alterations (such as drainage ditches, dams, dikes, dugouts, or fill) or subsurface alterations (such as tile drainage) present.

0.75

Condition Index Rating Pre-project

A surface alteration is present within the wetland as follows: (1) a drainage ditch with a bottom elevation at or above the hydric boundary; (2) a dam, dike, dugout, or any fill material affecting 25% or less of the wetland area,ANDNo subsurface alterations are present within the wetland.

A surface alteration is present within the wetland as follows: (1) a drainage ditch with a bottom elevation at or below the bottom of the wetland, (2) a dam, dike, dugout, or any fill material affecting 76% to 99% of the wetland area; (3) a constructed channel in lieu of the natural watercourse, vegetated,AND/ORSubsurface alterations (such as drain tile) into and through wetland, with some saturation remaining as evidenced by the presence of remnant hydrophytes.

0 Cultural alterations to the wetland are present such that all wetland hydrology has been eliminated. Alterations include channelization and lining, or complete diversion or drainage of surface and/or subsurface water sources.

0.01

0.5 A surface alteration is present within the wetland as follows: (1) a drainage ditch with a bottom elevation at or below the hydric boundary but above the bottom of the wetland; (2) a dam, dike, dugout, or any fill material affecting 26% to 50% of the wetland area,ANDNo subsurface alterations are present within the wetland.

0.25 A surface alteration (such as a dam, dike, dugout, or fill) is present within the wetland, and impacts from 51 to 75% of the wetland area.




Appendix A


0.25

0.1 Significant evidence of sedimentation throughout the wetland, as evidenced by the presence of rills, sediment fans or bars, and nearly complete burial of detritus and plants. Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. Conventional tillage is common, and ephemeral or perennial gullies may be present on uplands. Best management practices lacking to control erosion.

Significant evidence of sedimentation throughout most (> 75%) of the wetland, as evidenced by the presence of rills, sediment fans or bars, partial to nearly complete burial of detritus, or burial of plant crowns and partial burial of stems. Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. A buffer is typically absent. Tillage may occur throughout most (> 50%) of the wetland in most years.

Pronounced rise in bottom elevation of wetland due to sedimentation, resulting in the loss of wetland vegetation and/or hydrology. Wetland has been completely silted full.

0.5 Evidence of sedimentation throughout most (50 to 75%) of the wetland, as evidenced by the presence of rills, sediment fans or bars, partial burial of detritus, or accumulations along plant stems. Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. Tillage may be into or through buffer and into the outer edge of the wetland.

0

Vsed: Sediment DepositionDefinition: The presence or absence of culturally accelerated (eccessive) sedimentation within the channel (where applicable) and the floodplain wetland. Direct filling in the wetland does not count as sediment and is addressed under Hydrology Alterations. If fill is present, only evaluation that portion of the wetland that is intact. Assess possible sediment deposition near the edge of the wetland and toe of the adjacent slopes.

0.75 Evidence of sedimentation within less than half of the wetland area in the form of small rills, sediment fans or bars, or thin silt deposits on detritus.

No visual evidence of culturally accelerated sedimentation within the wetland or stream channel. (Note: Wetlands within well-connected floodplains may receive significant amounts of "natural" sedimentation during specific flood event.)

1.0

Assessment area: Stream reach and adjacent floodplain wetlands.Condition Index Rating Pre-project Post-project Project w/ conditions




Appendix A


1.00.750.5

0.25

1.00.750.5

0.250.10

Assessment area: Stream reach and immediately adjacent floodplain wetlands

510 105-9 115

Project w/ conditions

10 510

Native wetland species comprise 26 to 50 percent of the total vegetation present in the wetland.

3020

00015


Definition: The percentage of appropriate native wetland species (OBL, FACW, FAC) present in the stream reach and/or wetland, as indicated by the top five dominant species present on site, or by a more extensive species survey.

Native wetland species comprise 76 to 100 percent of the total vegetation present in the wetland. Condition Index RatingAssessment area: Stream and adjacent floodplain wetlands

205

100

2510

50 3090 15

Vnbuff: Buffer Continuity and Width

Native wetland species comprise 1 to 10 percent of the total vegetation present in the wetland;ORA single dominant plant species (native or non-native) comprise a monotypic invasive stand within the wetland (i.e. reed canarygrass, cattails, etc.).

Summary Rating for Buffer Continuity and Width 5-20 <540-5960-7980-99

Definition: The two components for this variable include continuity and width of permanently vegetated buffer adjacent to the wetland. Buffer continuity and width are interrelated as shown by the table below. Continuity is the estimated percentage of the wetland perimeter which is bordered by permanent vegetated buffer. When buffer width is >100 ft use 100 ft for the width at that point . Width is the average of multiple points surrounding the wetland and should be estimated based only on those areas where a buffer of permanent vegetation is present. The starting point is at the normal high water mark or the top of the bank measured perpendicular outward. Aerial photos and field investigations can be used. The point on the table at which these figures intersect is the summary rating to use for these two components. Correlate the summary rating to the 0 to 1.0 index rating.

Pre-project Post-project

Summary rating is 0 OR No buffer of permanent vegetation is present.

Vnplant: Native Plant Composition

100

0.1Native wetland species comprise 11 to 25 percent of the total vegetation present in the wetland.

Cont(%) 20-39

010

Summary Rating of 20 - 39


5


0 0 00



020 0

<5 00

100

Wetland is unvegetated. OR Wetland is completely dominated by non-wetland plants.

0

3040 30

100

5080

706075

10-24

50-74 6075-99

20Wid

th(ft

)

Project w/ conditionsCondition Index Rating Pre-project Post-project

5025-49

40




Appendix A


Assessment area: Area indundated by periodic out of bank flood events.

Definition: The topographic roughness of the floodplain, excluding the effects vegetation and other biotic factors have on that surface. Components are important in terms of velocity reduction of surface water flow and surface water storage.

Condition Index Rating Pre-project Post-project Project w/ conditions

Evidence of manipulations or activities in the flood plain area that have had a smoothing effect on the surface (such as cut and/or fill activities, cultivation, etc.),AND51 to 75% of the flood plain area is affected.

0.1 Evidence of manipulations or activities in the flood plain area that have had a smoothing effect on the surface (such as cut and/or fill activities, cultivation, etc.),AND76 to 95% of the flood plain area is affected.

0 Greater than 95% of the flood plain has been manipulated such that the surface is smooth and regular (as from fill and leveling for pavement, channel lining, etc.)

1.0 Natural conditions occur in the flood plain area as evidenced by irregular, uneven surfaces (undulating conditions from meander scars, sediment bars, or hummocks). No evidence of any manipulations that would result in a smooth surface (such as cut/fill activities, cultivation, etc.).

0.75 Evidence of manipulations or activities in the flood plain area that have had a smoothing effect on the surface (such as cut and/or fill activities, cultivation, etc.), AND 1 to 25% of the flood plain area is affected; ORExcessive “hoof action” (trampling) by livestock has occurred throughout the flood plain, such that naturally-occurring features have been obscured.


0.25

Vtopo: Topography of Floodplain




Appendix A


Pre-project Post-projectAssessment area: Area indundated by periodic out of bank flood events.

Project w/ conditionsCondition Index Rating

0 Urban, semi-pervious, or impervious surface resulting in maximum overland flow and a high rate of delivery to the wetland.

0.25 Permanent native or non-native pasture which has been severely over-grazed, with significant (>50%) bare ground, low plant vigor, and evidence of soil erosion;ORNo-till or minimum till row crop, continuous minimum till small grain.

0.5

0.1 Conventional tillage small grain or row crop;ORInputs/overflow from cultural activities (such as from industry and urbanization).

Permanent native or non-native pasture which has been historically over-grazed, with some (<50%) bare ground and low plant vigor;ORNo-till small grain;ORMinimum till small grain in a grass/legume rotation.

1.0 Well managed, permanently vegetated native plant communites. Management allows for adequate plant recovery time between grazing periods.

0.75 Permanent vegetation under a system of management such as: Native species under season-long grazing with moderate use;ORIdle non-native grassland; ORPermanent native or non-native hayland.

Definition: Rate the land use and condition of the majority of the topographic floodplain. Aerial photography and visual observations should be used to determine the dominant land use within the floodplain. Select the condition index rating that most closely matches the dominant land use type.

Vfuse: Floodplain Land Use




Appendix B


Post-Project With Conditions

Minimal Effect decision: No Minimal Effect granted

Vmod

Minimal Effect threshold is 0.10 (There must be less than a 0.10 decrease for BOTH Flood Attenuation and Wildlife Habitat from Pre-Project conditions)

Wildlife Habitat = {3(Water Storage Index) + 2[square root of (Vbuff X Vnplant)] + Vdens} then divide by 6

Water Storage =Final Rating

Final Rating

Notes:

[3(Vhalt) + 2 (Vsour) + square root of (Vmod X Vsed)] then divide by 6

Vegetation Density

Wetland Modifications

Vsour Source Area of Flow

Vdens

Sediment Deposition



Vbuff

Vsed

Proposed Action

Vhalt

Vnplant





Post-Project


Playa Wetlands Functional Assessment Date:

Planner:Landowner:Site Conditions:

Pre-Project


County:Location:

Playa Wetlandspage 1 of 6



Appendix B

0.5

0.01


0

0.25

Natural conditions present with no physical alteration(s) or excavations within the wetland and no alteration(s) to the natural outlet elevation with no change to wetland water regime class or size;ORWetland has been fully restored.Pits and other man-made excavations within the wetland hold <10% of the total water volume;ORBottom of constructed outlet(s) is at least 2 feet above the bottom elevation of the wetland

Pre-project Post-project

Pits and other man-made excavations within the wetland hold 10 - <25% of the total water volume.

Pits and other man-made excavations within the wetland hold 25 - <50% of the total water volume;ORBottom of constructed outlet(s) is at least 1 feet above the bottom elevation of the wetland.

Condition Index Rating

Pits and other man-made excavations within the wetland hold 50 - <75% of the total water volume.

Constructed pits or outlet at or below the lowest elevation of the wetland results in removal of >75% of total water volume.

Playa Wetlands Functional Assessment

0.75

Measurement Condition IndexVhalt: Hydrology Alterations

1.0

Definition: The measurement of features which remove water from the wetland (within the hydric soil footprint). This includes drainage ditches, tile lines, deep road ditches, reuse or concentration pits, and alteration of natural outlets or overflows.Assessment area: Wetland and infrastructure impacting hydrology (pit, drain, etc.)




Appendix B

Playa Wetlands Functional AssessmentMeasurement Condition Index

1.0Condition Index Rating Pre-project Post-project Project w/ conditionsAssessment area: Wetland and toe of the adjacent slopes.

0.25

Evidence of sedimentation throughout most (50 to 75%) of the wetland, as evidenced by the presenceof rills, sediment fans or bars, partial burial of detritus, or accumulations along plant stems,AND/ORSediment thickness is 3 to < 6 inches.Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. Tillage has been into or through buffer and into the outer edge of the wetland.

0.1 Significant evidence of sedimentation throughout the wetland, as evidenced by the presence of rills, sediment fans or bars, and nearly complete burial of detritus and plants,AND/ORSediment thickness is 9 to 12 inches.Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. Conventional tillage is common, and ephemeral or perennial gullies may be present on uplands. Best management practices lacking to control erosion.

0 Pronounced rise in bottom elevation of wetland due to sedimentation, resulting in the loss of wetland vegetation and/or hydrology. Typical thickness of sediment is > 12 inches;ORWetland has been completely filled (such as in or around urban areas).

Vsed: Sediment DepositionDefinition: The presence or absence of culturally accelerated (eccessive) sedimentation within the wetland. Direct filling in the wetland does not count as sediment and is addressed under Hydrology Alterations. If fill ispresent, only evaluation that portion of the wetland that is intact.

No visual evidence of culturally accelerated sedimentation within the wetland.

Significant evidence of sedimentation throughout most (> 75%) of the wetland, as evidenced by the presence of rills, sediment fans or bars, partial to nearly complete burial of detritus, or burial of plant crowns and partial burial of stems,AND/ORSediment thickness is 6 to < 9 inches.Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. A buffer is typically absent. Tillage has occurred throughout most (> 50%) of the wetland in most years

0.75 Evidence of sedimentation within less than half of the wetland area in the form of small rills, sediment fans or bars, or thin silt deposits on detritus,AND/ORSediment thickness is < 3 inches.

0.5




Appendix B


1.00.750.50.25

1.00.750.50.250.10

Post-project

5

515


50-7425-49

2015

50

Native wetland species comprise 11 to 25 percent of the total vegetation present in the wetland. Native wetland species comprise 1 to 10 percent of the total vegetation present in the wetland;ORA single dominant plant species (native or non-native) comprise a monotypic invasive stand within the wetland (i.e. reed canarygrass, cattails, etc.).

0.1


Project w/ conditionsPre-project


10-24

75-99

Cont(%)≥100


0 Wetland is unvegetated. OR Wetland is completely dominated by non-wetland plants.

Assessment area: Buffer zone adjacent to wetlandProject w/ conditions

<5 000 0 00

10

60-7980-99


50

020

5-90

0


00

100 <5

80706075

90

Summary Rating for Buffer Continuity and Width 5-2020-3940-59


Definition: The percentage of appropriate native wetland species (OBL, FACW, FAC) present in the river reach and/or wetland, as indicated by the top five dominant species present on the site, or by a more extensive species survey.


Assessment area: WetlandCondition Index Rating Post-project

1060 50

20

003040 30

100

151010 10





10

Wid

th(ft

)

10

15

5

30403020

25

Definition: The two components for this variable include continuity and width of permanently vegetated buffer adjacent to the wetland. Buffer continuity and width are interrelated as shown by the table below. Continuity is the estimated percentage of the wetland perimeter which is bordered by permanent vegetated buffer. When buffer width is >100 ft use 100 ft for the width at that point. Width is the average of multiple points surrounding the wetland and should be estimated based only on those areas where a buffer of permanent vegetation is present. The starting point is at the normal high water mark or the top of the bank measured perpendicular outward. Aerial photos and field investigations can be used. The point on the table at which these figures intersect is the summary rating to use for these two components. Correlate the summary rating to the 0 to 1.0 index rating.




Appendix B


1.00.750.50.250.10


Post-project

1.0 Percent of the source area for the wetland that is intact is between 90 and 110 percent of original or natural source area.

Vdens: Vegetation Density

Assessment area: Watershed


Definition: The abundance of actively growing plants throughout the wetland - (not including annually planted agricultural crops). If different conditions exist on different parts of the wetland, estimate a value with consideration for the amount of area at each condition index.

Vsour: Source Area of Flow


No vegetation is present.

Canopy cover is >20 to 40, or >100 to 125 percent (overlapping canopy).

Canopy cover is >125 percent.

Canopy cover is 1 to 20 percent.

0.75 Percent of the source area for the wetland that is intact is between 70 and 89 percent OR 111 and 130percent of original or natural source area.

Condition Index Rating Pre-project Post-project

0 The upland source area is extremely altered such that almost all water flow to the wetland is eliminated (less than 10 percent of source area is intact).

Definition: The presence of alterations to the landscape which affect flow paths and rates of water to the wetland. This includes reuse pits in uplands, county roads, terraces, etc. which reduce the watershed area. An assessment of man-made alterations to the wetland watershed that increase the size of the source area oflow should also be made due to impacts to hydrology of the wetland. Use topographic maps, aerial photos, soil surveys, and on-site inspection to evaluate the impacts.

Percent of the source area for the wetland that is intact is between 30 and 49 percent of original or natural source area.

0.5 Percent of the source area for the wetland that is intact is between 50 and 69 percent OR more than 131 percent of original or natural source area.

0.01 Percent of the source area for the wetland that is intact is between 10 and 29 percent of original or natural source area.

0.25

Canopy cover is >40 to 60, or >80 to 100 percent.

Canopy cover is >60 to 80 percent.

Assessment area: Wetland




Appendix B


0.1

Project w/ conditionsAssessment area: WetlandCondition Index Rating Pre-project Post-project

0.75 Dike or fill bisects the wetland area and the amount of isolated wetland is proportional to the amount of the isolated catchment area;ORDike has an unrestricted culvert(s) with the invert at or below natural grade. Increased flows to the wetland corrects altered hydrology.

Dike(s) or fill bisect wetland and change the wetland water regime class (reduced hydrology).

0 Dike or artificial pumping keep the wetland dry;ORLand leveling or fill has raised the elevation of the bottom of the wetland above the temporary zone

0.5 Dike(s) with water control capability keep water on a wetland and does not change the wetland water regime class;ORIncreased flows from irrigation runoff or elevated groundwater levels but has not altered the natural water regime class and soil characteristics;

0.25 Increased flows from irrigation runoff or elevated groundwater levels has altered the natural water regime class and soil characteristics;AND/ORSediment or soil ridge ponds shallow water outside of the wetland

1.0 Natural conditions present with no dikes or fill within the wetland that restrict or redirect flow or changethe wetland water regime class and no pumping or irrigation tailwater additions;ORWetland has been fully restored.

Vmod: Wetland ModificationsDefinition: The presence of constructed features such as dikes or fill which redirect water within the wetlandor an artificial increase or decrease in hydrology caused by irrigation runoff or pumping, respectively.




Appendix C


Minimal Effect threshold is 0.10 (There must be less than a 0.10 decrease for BOTH Flood Attenuation and Wildlife Habitat from Pre-Project conditions)Notes: Post-Project

Sediment Deposition




Final Rating

Final Rating

Pre-Project

Post-Project






Wooded Riverine Functional Assessment Date:

Planner:County:

Location:

Site Conditions:

Proposed Action

Landowner:

the square root of (Hr x Hw)Flood Attenuation =

*Vhalt =[4(Vhalt) + (Vsed + Vtopo)/2 + (Vbuff + Vfuse + Vstrat)/3] then divide by 6

Wildlife Habitat = [3(Vhalt) + Vnplant + (Vbuff + Vfuse + Vstrat)/3 + (Vsed + Vtopo)/2] then divide by 6

Vstrata

Vfuse Floodplain Land Use

Vegetative Strata

Vbuff

Vtopo Topography of Floodplain

use for calculating

Vhalt

Vsed

Vnplant

Hydrology AlterationsVhalt*

River HydrologyHr

Hw Wetland Hydrology

With Conditions

Wooded Riverinvepage 1 of 8



Appendix C

Wooded Riverine Functional Assessment

0.75

0.5

Measurement Condition IndexHr: River Hydrology

1.0

A water impoundment structure is situated downstream from the stream segment/linear wetland such that wetland hydrology has been enhanced or degraded beyond what it would normally be. No structures are present parallel to or upstream that would affect hydrology or hydrology impacted <25%. Any bank armor material is installed using bio-engineering techniques and is confined to a specific point on the river bank.One or more surface alterations (see list in 1.0 rating above) are present at a distance greater than 1/4 mile (1,320 feet) parallel to or upstream from the stream/linear wetland. Such alteration(s) partiallydivert (>25 - 50%) or retard the flow of surface water, particularly water from high flow events, away from the wetland. No subsurface alterations are present. Out of bank flow frequency occurs once every 3 to 10 years on average.


One or more surface alterations (see list in 1.0 rating above) are present at a distance greater than 1/8 mile (660 feet) up to 1/4 mile (1,320 feet) parallel to or upstream from the stream/linear wetland. Such alteration(s) partially divert (>50 - 75%) or retard the flow of surface water, particularly water from high flow events, away from the wetland. No subsurface alterations are present. Bank armor (if present) consists primarily of rock or metal and is confined to a specific point on the river bank. Out ofbank flow frequency occurs once every 11 to 25 years on average.

Definition: The presence of man-made, surface and/or subsurface alterations that are on the floodplain within or immediately adjacent to the river segment/linear wetland. These alterations primarily impact the hydrology of the river segment/linear wetland. Surface alterations may include channelization, armored banks, dams/dikes, levees, and severely degraded channels . Subsurface alterations are not common but may include large tile drainage systems. Flood plain alterations within 1/4 mile (1,320 feet) parallel to or upstream are considered significant to hydrology and must be considered.

One or more surface alterations (see list in 1.0 rating above) are present within 1/8 mile (660 feet) parallel to or upstream from the stream/linear wetland. Such alteration(s) are designed to divert or retard >75% of the surface water flow, particularly water from high flow events, away from the wetland. Bank armor (if present) consists primarily of rock or metal and used across a majority of the reach within the assessment area. Out of bank flow frequency occurs once every 26 or more years.AND/ORA subsurface drainage feature is used to contain the flow of the river for a distance greater than 100 feet.

Flood plain hydrology has been altered such that all surface and/or subsurface flow to the wetland hasbeen eliminated. (Alterations include channelization and lining, or complete diversion or drainage of surface and/or subsurface water sources.)

0.01

0

0.25

Flood plain has not been physically manipulated. No surface alterations (such as constructed channels, armored banks, dams, dikes, levees, diversions, dugouts, fill, or degraded channels) or subsurface alterations (such as tile drainage) present. Out of bank flow frequency averages at least once every 2 years to connect river to floodplain.

Assessment area: Stream reach and adjacent floodplain including alterations 1/4 mile above and below stream reach being assessed.

Pre-project Project w/ conditionsPost-project

Wooded Riverinepage 2 of 8



Appendix C

Wooded Riverine Functional AssessmentMeasurement Condition Index


0.01

Hw: Wetland HydrologyDefinition: The presence of man-made, surface and/or subsurface alterations that are within or adjacent to wetlands located on the floodplain but not within the flowing channel. These alterations primarily impact the hydrology of the wetland. Surface alterations may include shallow ditches, fill, or dams/dikes. Subsurface alterations may include tile drainage or ditches greater than two feet in depth.

1.0 Wetland has not been physically manipulated. No surface alterations (such as drainage ditches, dams, dikes, dugouts, or fill) or subsurface alterations (such as tile drainage) present.

0.75 A surface alteration is present within the wetland as follows: (1) a drainage ditch with a bottom elevation at or above the hydric boundary; (2) a dam, dike, dugout, or any fill material affecting 25% or less of the wetland area,ANDNo subsurface alterations are present within the wetland.

A surface alteration is present within the wetland as follows: (1) a drainage ditch with a bottom elevation at or below the bottom of the wetland, (2) a dam, dike, dugout, or any fill material affecting 76% to 99% of the wetland area; (3) a constructed channel in lieu of the natural watercourse, vegetated,AND/ORSubsurface alterations (such as drain tile) into and through wetland, with some saturation remaining as evidenced by the presence of remnant hydrophytes.

0 Cultural alterations to the wetland are present such that all wetland hydrology has been eliminated. Alterations include channelization and lining, or complete diversion or drainage of surface and/or subsurface water sources.

Assessment area: Wetlands located within adjacent floodplain. If there are no wetlands present in the assessment area then give this variable the same Condition Index Rating as River Hydrology.

0.5 A surface alteration is present within the wetland as follows: (1) a drainage ditch with a bottom elevation at or below the hydric boundary but above the bottom of the wetland; (2) a dam, dike, dugout, or any fill material affecting 26% to 50% of the wetland area,ANDNo subsurface alterations are present within the wetland.

0.25 A surface alteration (such as a dam, dike, dugout, or fill) is present within the wetland, and impacts from 51 to 75% of the wetland area.




Appendix C


Significant evidence of sedimentation throughout the wetland, as evidenced by the presence of rills, sediment fans or bars, and nearly complete burial of detritus and plants. Indicator: Dominant land useadjacent to the wetland, or within the watershed area, is cropland. Conventional tillage is common, and ephemeral or perennial gullies may be present on uplands. Best management practices lacking to control erosion.

1.0 No visual evidence of culturally accelerated sedimentation within the wetland or stream channel. (Note: Wetlands within well-connected floodplains may receive significant amounts of "natural" sedimentation during specific flood event.)

0.75 Evidence of sedimentation within less than half of the wetland area in the form of small rills, sediment fans or bars, or thin silt deposits on detritus.

Project w/ conditionsPost-projectPre-project

Vsed: Sediment DepositionDefinition: The presence or absence of culturally accelerated (eccessive) sedimentation within the channel (where applicable) and the floodplain wetland. Direct filling in the wetland does not count as sediment and is addressed under Hydrology Alterations. If fill is present, only evaluation that portion of the wetland that is intact. Assess possible sediment deposition near the edge of the wetland and toe of the adjacent slopes.


Evidence of sedimentation throughout most (50 to 75%) of the wetland, as evidenced by the presenceof rills, sediment fans or bars, partial burial of detritus, or accumulations along plant stems. Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. Tillage may be into or through buffer and into the outer edge of the wetland.

0.25

Pronounced rise in bottom elevation of wetland due to sedimentation, resulting in the loss of wetland vegetation and/or hydrology. Wetland has been completely silted full.

0.1

0

Assessment area: River reach and adjacent floodplain wetlands.

Significant evidence of sedimentation throughout most (> 75%) of the wetland, as evidenced by the presence of rills, sediment fans or bars, partial to nearly complete burial of detritus, or burial of plant crowns and partial burial of stems. Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. A buffer is typically absent. Tillage may occur throughout most (> 50%) of the wetland in most years.

0.5




Appendix C


1.00.750.50.25

1.00.750.50.250.10




100 <5

Condition Index Rating Project w/ conditions


Wetland is unvegetated. OR Wetland is completely dominated by non-wetland plants.


Definition: The two components for this variable include continuity and width of permanently vegetated buffer adjacent to the wetland. Buffer continuity and width are interrelated as shown by the table below. Continuity is the estimated percentage of the wetland perimeter which is bordered by permanent vegetated buffer. When buffer width is >100 ft use 100 ft for the width at that point. Width is the average of multiple points surrounding the wetland and should be estimated based only on those areas where a buffer of permanent vegetation is present. The starting point is at the normal high water mark or the top of the bank measured perpendicular outward. Aerial photos and field investigations can be used. The point on the table at which these figures intersect is the summary rating to use for these two components. Correlate the summary rating to the 0 to 1.0 index rating.Assessment area: River reach and immediately adjacent floodplain wetlands

Definition: The percentage of appropriate native wetland species (OBL, FACW, FAC) present in the river reach and/or wetland, as indicated by the top five dominant speciess present on the site, or by a more extensive species survey.

0

5

1010

Wid

th(ft

)

10

15≥100

Post-project

75

10-2425-49

75-99


252015

80 403020

7060


Cont(%) 20-3940-5960-7980-99

3040 30

100


Pre-project

Condition Index RatingAssessment area: River reach and adjacent floodplain wetlands

Post-projectPre-project


50

0

50-74

<5 00

60 50

5

Summary Rating for Buffer Continuity and Width 5-20

0

0

50 30

10 10

90

20


020 15 10

000

510 5


0 0 005-9 1







Appendix C



0 Greater than 95% of the flood plain has been manipulated such that the surface is smooth and regular(as from fill and leveling for pavement, channel lining, etc.)

1.0 Natural conditions occur in the flood plain area as evidenced by irregular, uneven surfaces (undulatingconditions from meander scars, sediment bars, or hummocks). No evidence of any manipulations that would result in a smooth surface (such as cut/fill activities, cultivation, etc.).

0.75 Evidence of manipulations or activities in the flood plain area that have had a smoothing effect on the surface (such as cut and/or fill activities, cultivation, etc.), AND 1 to 25% of the flood plain area is affected; ORExcessive “hoof action” (trampling) by livestock has occurred throughout the flood plain, such that naturally-occurring features have been obscured.



Vtopo: Topography of Floodplain

Project w/ conditionsAssessment area: Area indundated by periodic out of bank flood events.Condition Index Rating Pre-project Post-project

Definition: The topographic roughness of the flood plain, excluding the effects vegetation and other biotic factors have on that surface. Components are important in terms of velocity reduction of surface water flow and surface water storage.




Appendix C


Assessment area: Area indundated by periodic out of bank flood events.Project w/ conditionsPre-project Post-project

0.5 Permanent native or non-native pasture which has been historically over-grazed, with some (<50%) bare ground and low plant vigor;ORNo-till small grain;ORMinimum till small grain in a grass/legume rotation.

Vfuse: Floodplain Land Use

1.0 Well managed, permanently vegetated native plant communites. Management allows for adequate plant recovery time between grazing periods.

0.75 Permanent vegetation under a system of management such as: Native species under season-long grazing with moderate use;ORIdle non-native grassland; ORPermanent native or non-native hayland.


Definition: Rate the land use and condition of the majority of the topographic floodplain (excluding the river segment; adjacent wetlands; and associated buffers for each). Aerial photography and visual observations should be used to determine the dominant land use within the floodplain. Select the condition index rating that most closely matches the dominant land use type.

0.25 Permanent native or non-native pasture which has been severely over-grazed, with significant (>50%)bare ground, low plant vigor, and evidence of soil erosion;ORNo-till or minimum till row crop, continuous minimum till small grain.

0.1 Conventional tillage small grain or row crop;ORInputs/overflow from cultural activities (such as from industry and urbanization).

0 Urban, semi-pervious, or impervious surface resulting in maximum overland flow and a high rate of delivery to the wetland.




Appendix C


1.0

0

Assessment area: Area indundated by periodic out of bank flood events.


Stream Order No. Strata Vegetative Type

Vstrat: Vegetative StrataDefinition: The rating is based on the number of vegetative strata present that are appropriate for the site and the percentage of the assessment area (buffer and topographic floodplain) occupied by those strata. If different conditions exist on different parts of the assessment area, assess the dominant cover type within thebuffer zone.

Rivers and adjacent wetlands may contain from one to three vegetative strata, depending upon river hydrology, position/location of the wetland within the hydrologic unit, and geographical region of the state. These strata, for purposes of simplicity, are defined as follows:1. Herbaceous layer -- the layer consisting of grasses, sedges, forbs, etc. 2. Shrub layer -- the layer consisting of shrubs such as chokecherry, rough-leaved dogwood, false indigo, etc3. Tree layer -- the layer consisting of mature trees such as willows, cottonwoods, etc.

Vegetative stratification and composition within riverine ecosystems is more complex than this variable will address. The following guidelines can be used to determine the number of strata that should be present under natural conditions in a given floodplain at a given position in the hydrologic unit. Comparison to a reference standard site in the surrounding proximity is the preferred approach. The attached map showing riparian buffer vegetation recommendations also provides general information on the suitability of trees to different regions of the state.

Strata

0.75

Lower 50% of 2nd Order and beyond 3 Herb/Shrub/Tree

All appropriate strata are present only within the buffer zone for the river edge and adjacent wetlands. OR One appropriate strata is missing but 50% or more of the floodplain contains permanent vegetation.

All appropriate strata are present on 50% or more of the floodplain within the assessment area.

0.1 Permanent vegetation is present in small portions of the floodplain (substantially less than 50%). OR Only small portions of the buffer zone contains permanent vegetation and/or buffers do not meet minimum required widths (filter strip - 20 feet; riparian forest buffer - 35 feet).Any permanent vegetation that is present consists of less than 1% of the assessment area.

0.5 One appropriate strata is missing and only the buffer zone contains permanent vegetation. OR More than one appropriate strata is missing but 50% or more of the floodplain contains permanent vegetation.

0.25 More than one appropriate strata is missing and only the buffer zone contains permanent vegetation.

Mid 20% to 50% of 2nd Order 2 Herb/Shrub1st Order and Upper 20% of 2nd 1 Herb




Appendix D

Minimal Effect decision: No Minimal Effect granted





Sedimentation Deposition



Vbuff

Vhalt

Vsed

Vnplant

Sandhills Wetlands Functional Assessment Date:

Planner:

Pre-Project

Post-Project



Site Conditions:


County:Location:

Proposed Action

Landowner:

Ground Water Storage =Final Rating

Wildlife Habitat =

Post-Project


Final Rating

With ConditionsNotes:

Vdens

Vsour

Vegetation Density

Source Area of Flow

[2(Vhalt) + (Vsed + Vsour)/2] then divide by 3

[3(Water Storage Index) + Vnplant + Vdens + Vbuff] then divide by 6

Sandhills Wetlandspage 1 of 5



Appendix D

Project w/ conditionsPost-project

Sandhills Wetlands Functional Assessment

0.75

0.5


1.0

Assessment area: Wetland and infrastructure impacting hydrology (pump, drain, etc.)Condition Index Rating Pre-project

Definition: The presence of a constructed surface or subsurface drainage feature or fill within the wetland. Surface: The depth of the surface drain and/or depth of fill within the wetland impacts wetland ground water surface elevation and movement of surface water through the wetland. ORSubsurface: The impact of the subsurface drain on the wetland is determined by its relative elevation and distance from the wetland (lateral effects). Subsurface drains outside of the influence of the wetland but within the watershed are considered under the Source Area of Flow variable.

0.01

0

0.25

No surface drains or fill present; no dikes that restrict or redirect flow; and no pumping out of or into the wetland. Excavation (pit) affects less than 1% of the wetland area. ORNo subsurface drain present. -OR- If there is a nearby subsurface drainage feature (outside of the wetland), the distance to such feature is equal to or greater than that identified as the lateral effect in the approved county lateral effect table for the soil type. Surface drains exist within the wetland but do not exit the wetland. Fill exists within the wetland but affects less than 10 percent of the wetland. -OR- A dugout or dam/dike exists within the wetland but affects less than 10 percent of the wetland area.ORThe distance to a nearby subsurface drainage feature is less than the lateral effect distance identified, with an estimated corresponding impact to the wetland size and/or width of less than or equal to 25 percent.A narrow surface drain exits the wetland, but elevation difference between the bottom of the ditch and the normal water level of the wetland is less than 1 foot. -OR- Fill exists within the wetland and affects more than 10 percent, but less than 50 percent, of the wetland. Pumping occurs (out of or into) but it does not change the water regime class. ORThe distance to a nearby subsurface drainage feature is less than the lateral effect distance identified, with an estimated corresponding impact to the wetland size and/or width of greater than 25 to less than or equal to 50 percent.

A surface drain exits the wetland that is deeper than the bottom of the wetland. -OR- Fill or an excavation (pit) exists within the wetland and affects 75 percent or more of the wetland area. -OR- Pumping occurs (out of or into) and completely removes surface water or impounds water 3 feet (or more) deeper than normal water level. ORSubsurface drainage feature is located within the wetland or close enough to impact the wetland size and/or width greater than 75 percent. Saturated conditions have been severely impacted but still occur seasonally. A surface drain exits the wetland that is > 3 feet deeper than the bottom of the wetland. -OR- Wetland completely filled. ORSaturated conditions non-existent due to subsurface drainage.

A surface drain exits the wetland and elevation difference between the bottom of the ditch and the normal water level of the wetland is between 1 and 2 feet. -OR- Fill or an excavation (pit) exists within the wetland and affects 50 percent, but less than 75 percent of the wetland area. -OR- Pumping occurs (out of or into) and changes the water regime class. ORThe distance to a nearby subsurface drainage feature is less than the lateral effect distance identified, with an estimated corresponding impact to the wetland size and/or width of greater than 50 to less than or equal to 75 percent.




Appendix D

Sandhills Wetlands Functional AssessmentMeasurement Condition Index

1.0Post-projectCondition Index Rating Pre-project

Definition: The presence or absence of culturally accelerated (eccessive) sedimentation within the wetland. Direct filling in the wetland does not count as sediment and is addressed under Hydrology Alterations. If fill is present, only evaluation that portion of the wetland that is intact. Assessment area: Wetland and toe of the adjacent slopes.


Vsed: Sediment Deposition


Significant evidence of sedimentation throughout most (> 75%) of the wetland, as evidenced by the presence of rills, sediment fans or bars, partial to nearly complete burial of detritus, or burial of plant crowns and partial burial of stems,AND/ORSediment thickness is 6 to < 9 inches.Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. A buffer is typically absent. Tillage has occurred throughout most (> 50%) of the wetland in most years.



0.5 Evidence of sedimentation throughout most (50 to 75%) of the wetland, as evidenced by the presence of rills, sediment fans or bars, partial burial of detritus, or accumulations along plant stems,AND/ORSediment thickness is 3 to < 6 inches.Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. Tillage has been into or through buffer and into the outer edge of the wetland.


0.25




Appendix D


1.00.750.5

0.25

1.00.750.5

0.250.10

Project w/ conditionsAssessment area: Buffer zone adjacent to wetlandCondition Index Rating Pre-project Post-project

10


0

Post-project





Definition: The percentage of appropriate native wetland species (OBL, FACW, FAC) present in the river reach and/or wetland, as indicated by the top five dominant species present on the site, or by a more extensive

Native wetland species comprise 76 to 100 percent of the total vegetation present in the wetland. Condition Index Rating



Pre-project

10

15

5

403020

30

10100 0


5

Wid

th(ft

)

520

6050

7590

15

252015

50

50

15 10

1010

8060

70100




<5 0

10-24

Summary Rating for Buffer Continuity and Width 5-2020-3940-5960-7980-99100 <5Cont(%)

20 0


00003040 30

75-99≥100

50-74


0 00


5-90


25-49





Appendix D


0.5

0


Canopy cover is >60 to 80 percent, or >125 percent, -AND-Wetland is intact (either undisturbed or has not been tilled or otherwise disturbed for 20 years or more).


0.1 The dominant surface and subsurface flow path of water in the watershed source area has been altered to affect the flow of water to the wetland (such as by tiling, terraces, or surface irrigation return). Greater than 50 to 95 percent of the watershed area is impacted.ANDThe alteration(s) changes the wetland subclass.

0.25

Post-project

The dominant surface and subsurface flow path of water in the watershed source area has been altered to affect the flow of water to the wetland (such as by tiling, terraces, or surface irrigation return). Greater than 50 to 95 percent of the watershed area is impacted.ANDThe alteration(s) does not change the wetland subclass.

Surface alterations occur within the watershed source area which impact overland flow into wetland (such as terraces or road right-of-ways with culverts allowing passage of water). Less than 20 percent of watershed area is impacted.ANDNo subsurface alterations or additions (identified in 5 above) are present. -OR- Center pivot irrigation is used within the wetland watershed source area.


1.0


0.75

Plants absent, no canopy cover (site is more disturbed than described above).

Canopy cover is >40 to 60 percent. -OR- Wetland is tilled infrequently (20% or less of all years).

0.25 Canopy cover is >20 to 40 percent. -OR- Wetland is tilled occasionally (>20% to <60% of all years). Hydrophytic vegetation normally returns to the site during wet periods when tillage is impossible.

0.1

0 Upland watershed source area extremely altered such that 95% or more of all water flow to wetland has been eliminated (such as from urbanization).

Definition: The physical alterations that exist within the area surrounding the wetland that defines the watershed source area.


1.0 No surface or subsurface alterations within the wetland watershed source area. (This includes surface alterations such as dams, terraces, and roads; subsurface alterations such as tile drains and ditches; and additional inputs such as irrigation and terrace outlets.)

0.75

0.5 Surface alterations occur within the watershed source area which impact overland flow into wetland (such as terraces or road right-of-ways which partially divert the flow of water to the wetland). Greater than 20 up to to 50 percent of watershed area is impacted.ANDNo subsurface alterations or additions (identified in 5 above) are present.


Canopy cover is >80 to 125 percent. -AND- Wetland is intact (either undisturbed or has not been tilled or otherwise disturbed for 20 years or more).


Canopy cover is 1 to 20 percent. -OR- Wetland is tilled most years (60% or more of all years). Growing hydrophytic vegetation may return to the site during wet periods when tillage is impossible.





Appendix E

[3(Vhalt) + Vdens + Vnplant + Vbuff] then divide by 6

Vdens

Vsour

Water Quality =

Vegetation Density

Source Area of Flow

[3(Vhalt) + Vdens + Vbuff + (Vsed + Vsour)/2] then divide by 6


Final Rating

Final Rating

Wildlife Habitat =



Notes:

Vnplant

Location:



Proposed Action

Landowner:Site Conditions:

Slope Wetlands Functional Assessment Date:

Planner:County:


Pre-Project

Post-Project

Post-Project With Conditions




Sedimentation Deposition



Vbuff

Vhalt

Vsed

Slope Wetlandspage 1 of 5



Appendix E

Project w/ conditionsCondition Index Rating Pre-project Post-project

A surface drain exists within the wetland that is greater than 2 feet in depth. -OR- The natural meandering flow path has been straightened, and out of bank flow will NOT occur for a 10 year, 24 hour storm.ORSubsurface drainage feature is located within the wetland or close enough to impact the wetland size and/or width greater than 75 percent. Saturated conditions have been severely impacted but still occur seasonally. Armored or lined channel, saturated conditions completely non-existent, or wetland completely filled. -OR- Saturated conditions non-existent (completely drained). ORFill exists within the wetland and affects 90 percent or more of the wetland area.

Definition: The presence of a constructed surface or subsurface drainage feature or fill within the wetland. Surface: The depth of the surface drain and/or depth of fill within the wetland impacts wetland ground water surface elevation and movement of surface water through the wetland. ORSubsurface: The impact of the subsurface drain on the wetland is determined by its relative elevation and distance from the wetland (lateral effects). Subsurface drains outside of the influence of the wetland but within the watershed are considered under the Source Area of Flow variable

0.01

0

0.25

No surface drains or fill present.ORNo subsurface drain present. -OR- If there is a nearby subsurface drainage feature (outside of the wetland), the distance to such feature is equal to or greater than that identified as the lateral effect in the approved county lateral effect table for the soil type. Fill exists within the wetland but affects less than 10 percent of the wetland. -OR- A dugout or dam exists within the wetland but affects less than 10 percent of the wetland area. -OR- A shallow grassed waterway exists and follows the natural meandering flow path.ORThe distance to a nearby subsurface drainage feature is less than the lateral effect distance identified,with an estimated corresponding impact to the wetland size and/or width of less than or equal to 25 percent. -OR- Development of the assessment area for livestock water (spring development) is planned. A narrow surface drain or gully exists within the wetland, but is less than 1 foot in depth. -OR- Fill exists within the wetland and affects more than 10 percent, but less than 50 percent, of the wetland. ORThe distance to a nearby subsurface drainage feature is less than the lateral effect distance identified,with an estimated corresponding impact to the wetland size and/or width of greater than 25 to less than or equal to 50 percent.

A surface drain or gully exists within the wetland, and is between 1 and 2 feet in depth. -OR- The natural meandering flow path has been straightened, and out of bank flow will occur for a 10 year, 24 hour storm. -OR- Fill or an excavation (pit) exists within the wetland and affects 50 percent or more of the wetland area. ORThe distance to a nearby subsurface drainage feature is less than the lateral effect distance identified,with an estimated corresponding impact to the wetland size and/or width of greater than 50 to less than or equal to 75 percent.

Slope Wetlands Functional Assessment

0.75

0.5


1.0

Assessment area: Wetland and area of lateral effects




Appendix E

Slope Wetlands Functional AssessmentMeasurement Condition Index

1.0Condition Index Rating Pre-project Post-project Project w/ conditions


0.25

Assessment area: Wetland and toe of the adjacent slopes.



0.5 Evidence of sedimentation throughout most (50 to 75%) of the wetland, as evidenced by the presenceof rills, sediment fans or bars, partial burial of detritus, or accumulations along plant stems,AND/ORSediment thickness is 3 to < 6 inches.Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. Tillage has been into or through buffer and into the outer edge of the wetland.

Vsed: Sediment DepositionDefinition: The presence or absence of culturally accelerated (eccessive) sedimentation within the wetland. Direct filling in the wetland does not count as sediment and is addressed under Hydrology Alterations. If fill ispresent, only evaluation that portion of the wetland that is intact.


Significant evidence of sedimentation throughout most (> 75%) of the wetland, as evidenced by the presence of rills, sediment fans or bars, partial to nearly complete burial of detritus, or burial of plant crowns and partial burial of stems,AND/ORSediment thickness is 6 to < 9 inches.Indicator: Dominant land use adjacent to the wetland, or within the watershed area, is cropland. A buffer is typically absent. Tillage has occurred throughout most (> 50%) of the wetland in most years




Appendix E


1.00.750.50.25

1.00.750.50.250.10



0 00

20 15 105

25-4910-24


75-99

5-90


≥100

50-74





<5 00


0


0000


Summary Rating for Buffer Continuity and Width 5-2020-3940-5960-7980-99100 <5




Definition: The percentage of appropriate native wetland species (OBL, FACW, FAC) present in the river reach and/or wetland, as indicated by the top five dominant species present on the site, or by a more extensive species survey.

Native wetland species comprise 76 to 100 percent of the total vegetation present in the wetland. Condition Index Rating Pre-project Post-projectAssessment area: Wetland

8060

706050

7550

90

3040 30

100

Assessment area: Buffer zone adjacent to wetland

151010 10


00

252015

50

520

Cont(%)

403020

30

5

1010

Wid

th(ft

)

10

15





Appendix E


0.5

0



Condition Index Rating Pre-project Post-project

The dominant surface and subsurface flow path of water in the watershed source area has been altered to affect the flow of water to the wetland (such as by tiling, terraces, or surface irrigation return). Greater than 50 to 95 percent of the watershed area is impacted.ANDThe alteration(s) does not change the wetland subclass.

Surface alterations occur within the watershed source area which impact overland flow into wetland (such as terraces or road right-of-ways with culverts allowing passage of water). Less than 20 percentof watershed area is impacted.ANDNo subsurface alterations or additions (identified in 5 above) are present. -OR- Center pivot irrigation is used within the wetland watershed source area.


Plants absent, no canopy cover (site is more disturbed than described above).

Canopy cover is >40 to 60 percent. -OR- Wetland is tilled infrequently (20% or less of all years).

0.25 Canopy cover is >20 to 40 percent. -OR- Wetland is tilled occasionally (>20% to <60% of all years). Hydrophytic vegetation normally returns to the site during wet periods when tillage is impossible

0.1 Canopy cover is 1 to 20 percent. -OR- Wetland is tilled most years (60% or more of all years). Growing hydrophytic vegetation may return to the site during wet periods when tillage is impossible


0.75

0 Upland watershed source area extremely altered such that 95% or more of all water flow to wetland has been eliminated (such as from urbanization).

Definition: The physical alterations that exist within the area surrounding the wetland that defines the watershed source area.


1.0 No surface or subsurface alterations within the wetland watershed source area. (This includes surface alterations such as dams, terraces, and roads; subsurface alterations such as tile drains and ditches; and additional inputs such as irrigation and terrace outlets.)

0.75


0.5 Surface alterations occur within the watershed source area which impact overland flow into wetland (such as terraces or road right-of-ways which partially divert the flow of water to the wetland). Greater than 20 up to to 50 percent of watershed area is impacted.ANDNo subsurface alterations or additions (identified in 5 above) are present.

Canopy cover is >80 to 125 percent. -AND- Wetland is intact (either undisturbed or has not been tilledor otherwise disturbed for 20 years or more).


0.1 The dominant surface and subsurface flow path of water in the watershed source area has been altered to affect the flow of water to the wetland (such as by tiling, terraces, or surface irrigation return). Greater than 50 to 95 percent of the watershed area is impacted.ANDThe alteration(s) changes the wetland subclass.

0.25

Canopy cover is >60 to 80 percent, or >125 percent, -AND-Wetland is intact (either undisturbed or has not been tilled or otherwise disturbed for 20 years or more).

1.0




Appendix F

EXISTING FUNCTIONAL

LEVEL2FUNCTION

INORGANIC AND ORGANIC CYCLING FUNCTIONS

3. Ground water recharge4. Ground water discharge

4. Export of Organic Carbon5. Organic carbon storage (soils w/ 8"or more OM only)

1. Maintain typical plant species of the native community2. Maintain typical layers of the natural plant community

PLANT AND ANIMAL FUNCTIONS

5. Maintain habitat quality, interspersion, travel corridors, etc.

(b) More than 7 days2. Velocity reduction

FUNCTIONAL ASSESSMENT WORKSHEET

Alteration as described above

Alteration with conditions described above

1. Mineral recycling Process

FUNCTIONAL EFFECTS1

HYDROLOGICAL FUNCTIONS1. Surface water storage (a) Up to 7 days

2. Remove dissolved elements and compounds3. Particulate retention (sediment and organic material)

3. Maintain typical accumulation of decomposing plant and animal matter

4. Maintain typical abundance of animals (vertebrates and invertebrates)

Location:

Proposed Action

Landowner:


Site Conditions:

Other Wetlands Functional Assessment Date:

Planner:County:

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Appendix F

1 (0) - No Effect; (-) - Reduced; (+) - Improved; (E) - Eliminated. Consider direct and indirect impacts2 (NA) - not applicable; (E) - exceptional; (H) - high; (M) - medium; (L) – low

Minimal effect decision (check "√" the appropriate description and decision):

Notes:

FUNCTIONEXISTING

FUNCTIONAL LEVEL2

FUNCTIONAL EFFECTS1

Alteration as described above

Alteration with conditions described above

Number of Functions Existing

Number of Existing Functions Reduced or EliminatedPercent of Existing Functions Reduced or Eliminated

E. All existing, identified functions are rated low. The effect is MINIMAL. (This situation will be very rare) Proceed with Step 7.

A. One or more existing, identified functions are rated exceptional and that function will be reduced or eliminated. The effect is NOT MINIMAL and does not qualify for a minimal effect exemption. MITIGATION WILL BE VERY DIFFICULT TO ACHIEVE. B. One or more existing, identified functions that are rated medium or high will be eliminated by the proposed action. The effect is NOT MINIMAL and does not qualify for a minimal effect exemption. Mitigation may be possible.C. No exceptional functions will be reduced or eliminated. No medium or high functions will be eliminated. Greater than 25% of the total number of existing functions will be reduced (or eliminated if a low function). The effect is NOT MINIMAL and does not qualify for a minimal effect exemption. Mitigation may be possible.

D. No exceptional functions will be reduced or eliminated. No medium or high functions will be eliminated. Less than 25% of the total number of existing functions will be reduced (or eliminated if a low function) then the effect is MINIMAL. Proceed with Step 7.

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Documents

NE-CPA-FSA-Worksheet-10 Nebraska Wetland Functional ......U.S. DEPARTMENT OF AGRICULTURE Natural Resources Conservation Service NE-CPA-FSA-Worksheet-10 2/09 Appendix A Definition: